Burden of deep vein thrombosis in the outpatient setting following major orthopedic surgery

BACKGROUND: Venous thromboembolism (VTE) is a known complication of major orthopedic surgery (MOS) with important clinical and economic consequences. Recently published orthopedic guidelines have focused on prevention of pulmonary embolism as a primary outcome, but deep vein thrombosis (DVT) occurrence should not be readily dismissed. OBJECTIVE: To describe the burden of DVT following hospital discharge for MOS by assessing the impact of DVT on costs and resource utilization from the third-party payer perspective. METHODS: Retrospective analysis used outpatient medical and pharmacy data from the PharMetrics Patient-Centric Database (January 1, 2002-March 31, 2006). Patients 18 years of age or older with a record of MOS were eligible for inclusion. Included patients were stratified based on the presence of a DVT during the first month after hospital discharge. Characteristics of the samples were described. The impact of DVT on total 6-month costs and resource utilization (readmissions, outpatient, emergency department visits) was assessed through statistical models. RESULTS: Of the 32,899 patients in the analysis, 1221 (3.71%) had a record of DVT during the first month following discharge for MOS. Compared with patients who did not develop DVT, patients who developed DVT postdischarge were slightly older (56.5 vs 55.8 y; p = 0.0127), had a higher occurrence of prior VTE (26.2% vs 3.4%; p < 0.0001), and had undergone recent surgical procedures other than MOS (73.0% vs 69.6%; p = 0.0116). After controlling for potential confounders, DVT was associated with a 22% and 740/6 increase in the average number of expected outpatient and emergency department visits, respectively, during the 6-month postdischarge period but did not significantly impact the number of readmissions. Furthermore, total 6-month costs were significantly higher for patients who developed DVT, with an incremental increase of over $2000. CONCLUSIONS: The burden of DVT following hospital discharge for MOS is substantial. Specifically, DVT increases total costs and outpatient and emergency department visits.